CHIKV Mutation Detail Information

Virus Mutation CHIKV Mutation D63A


Basic Characteristics of Mutations
Mutation Site D63A
Mutation Site Sentence Using this highly sensitive assay to analyze CHIKV nsP1 functionality, several mutations that severely reduced, but did not completely block, CHIKV replicase activity were identified: (i) nsP1 tagged at its N terminus with enhanced green fluorescent protein; (ii) mutations D63A and Y248A, blocking the RNA capping; and (iii) mutation R252E, affecting nsP1 membrane anchoring.
Mutation Level Amino acid level
Mutation Type Nonsynonymous substitution
Gene/Protein/Region nsP1
Standardized Encoding Gene nsP1
Genotype/Subtype -
Viral Reference -
Functional Impact and Mechanisms
Disease Chikungunya Fever    
Immune -
Target Gene -
Clinical and Epidemiological Correlations
Clinical Information -
Treatment -
Location -
Literature Information
PMID 31217251
Title Design and Use of Chikungunya Virus Replication Templates Utilizing Mammalian and Mosquito RNA Polymerase I-Mediated Transcription
Author Utt A,Rausalu K,Jakobson M,Mannik A,Alphey L,Fragkoudis R,Merits A
Journal Journal of virology
Journal Info 2019 Aug 28;93(18):e00794-19
Abstract Chikungunya virus (CHIKV) is a mosquito-borne alphavirus. It has a positive-sense RNA genome that also serves as the mRNA for four nonstructural proteins (nsPs) representing subunits of the viral replicase. Coupling of nsP and RNA synthesis complicates analysis of viral RNA replication. We developed trans-replication systems, where production of replication-competent RNA and expression of viral replicase are uncoupled. Mammalian and mosquito RNA polymerase I promoters were used to produce noncapped RNA templates, which are poorly translated relative to CHIKV replicase-generated capped RNAs. It was found that, in human cells, constructs driven by RNA polymerase I promoters of human and Chinese hamster origin performed equally well. In contrast, RNA polymerase I promoters from Aedes mosquitoes exhibited strong species specificity. In both mammalian and mosquito cells, novel trans-replicase assays had exceptional sensitivity, with up to 10(5)-fold higher reporter expression in the presence of replicase relative to background. Using this highly sensitive assay to analyze CHIKV nsP1 functionality, several mutations that severely reduced, but did not completely block, CHIKV replicase activity were identified: (i) nsP1 tagged at its N terminus with enhanced green fluorescent protein; (ii) mutations D63A and Y248A, blocking the RNA capping; and (iii) mutation R252E, affecting nsP1 membrane anchoring. In contrast, a mutation in the nsP1 palmitoylation site completely inactivated CHIKV replicase in both human and mosquito cells and was lethal for the virus. Our data confirm that this novel system provides a valuable tool to study CHIKV replicase, RNA replication, and virus-host interactions.IMPORTANCE Chikungunya virus (CHIKV) is a medically important pathogen responsible for recent large-scale epidemics. The development of efficient therapies against CHIKV has been hampered by gaps in our understanding of how nonstructural proteins (nsPs) function to form the viral replicase and replicate virus RNA. Here we describe an extremely sensitive assay to analyze the effects of mutations on the virus RNA synthesis machinery in cells of both mammalian (host) and mosquito (vector) origin. Using this system, several lethal mutations in CHIKV nsP1 were shown to reduce but not completely block the ability of its replicase to synthesize viral RNAs. However, in contrast to related alphaviruses, CHIKV replicase was completely inactivated by mutations preventing palmitoylation of nsP1. These data can be used to develop novel, virus-specific antiviral treatments.
Sequence Data -
Mutation Information
Note
Basic Characteristics of Mutations
  • Mutation Site: The specific location in a gene or protein sequence where a change occurs.
  • Mutation Level: The level at which a mutation occurs, including the nucleotide or amino acid level.
  • Mutation Type: The nature of the mutation, such as missense mutation, nonsense mutation, synonymous mutation, etc.
  • Gene/Protein/Region: Refers to the specific region of the virus where the mutation occurs. Including viral genes, viral proteins, or a specific viral genome region. If the article does not specifically indicate the relationship between the mutation and its correspondence, the main
  • Gene/Protein/Region studied in the article is marked.
  • Genotype/Subtype: Refers to the viral genotype or subtype where the mutation occurs. If the article does not specifically indicate the relationship between the mutation and its correspondence, the main Genotype/Subtype studied in the article is marked.
  • Viral Reference: Refers to the standard virus strain used to compare and analyze viral sequences.
Functional Impact and Mechanisms
  • Disease: An abnormal physiological state with specific symptoms and signs caused by viral infection.
  • Immune: The article focuses on the study of mutations and immune.
  • Target Gene: Host genes that viral mutations may affect.
Clinical and Epidemiological Correlations
  • Clinical Information: The study is a clinical or epidemiological study and provides basic information about the population.
  • Treatment: The study mentioned a certain treatment method, such as drug resistance caused by mutations. If the study does not specifically indicate the relationship between mutations and their correspondence treatment, the main treatment studied in the article is marked.
  • Location: The source of the research data.
Literature Information
  • Sequence Data: The study provides the data accession number.